The present invention relates to a multicolor fused decorative sheet used for a shower curtain, window affixed sheet, table runner, table cloth, substrate for bag, and so on and the manufacturing method and manufacturing apparatus thereof.
Hitherto, this kind of decorative sheet has a pattern printed or surface unevenness formed by embossing on the front or rear surface of a synthetic resin sheet to improve design characteristics. Further, bottom dye printing and top dye printing using an emboss roll are known, and in addition to these, there is a chemical embossing method for forming concave and convex patterns on the synthetic resin sheet with printing ink with a foam inhibitor such as trimellitic acid, or the like blended to suppress foaming on the printing ink adhering surface of a foam sheet (made of synthetic resin).
However, in the method using the emboss roll, the concave and convex patterns formed by the emboss roll are shallow in depth and are likely to wear out, thereby giving rise to a problem in that a porcelain-like glossy sheet is unable to be obtained. There is another problem in that when the a foamed sheet is used, since it has foamed portion on the surface, the strength is low and if the printing ink with the foam inhibitor blended is used, the porcelain-like gloss is unable to be obtained.
Therefore, the inventors have proposed a method for manufacturing a sheet with concave and convex patterns precisely formed and with glossiness provided in Japanese Patent No. 1669906 and Japanese Patent No. 1767264. In this method, a long-size base sheet with paste-form resin applied on one side is inserted between a metal cylinder equipped with a heater for gelation and a pressing roll, and is pressed, whereby concave and convex patterns are formed by the concavely carved patterns formed on one of the cylinder and the pressing roll. However, in recent years, demands for gorgeous decorative sheets with still more excellent design characteristics is increased.